Axial impact type rotary tool



y 1951 P. H. CARLSON ETAL 2,559,558

AXIAL IMPACT TYPE ROTARY TOOL Filed Sept. 26, 1946 10 Afl) 11-+ 66 11Lav f i '3 $77 I .52 fi Emu/WNW 3 PM E. 0%?

Patented July 3, 1951 AXIAL IMPACT TYPE ROTARY TOOL Paul H. Carlson andEdwin N. Carlson, St. Paul,

and Warren E. Carlson, Stillwater, Minn.

Application September 26, 1946, Serial No. 699,492

1 Claim. (Cl. 8152.3)

Our invention relates to an improvement in axial impact type rotary toolwherein it is desired to provide a simple and efficient means ofloosening screws and bolts.

The object of the present invention is to provide a simple apparatus forloosening screws and bolts and particularly those which are difiicult toloosen. Many screws and bolts become rusted in place so that extremedifiiculty is experienced in in a corresponding socket of a screw drivershank or socket wrench. As a result the cam portion may be fitted with aaxial screw driver shank for loosening screws and the like, or may beequipped with a socketwrench fitted for accommodating bolts or nuts ofvarious sizes.

These and other objects and novel features of our invention will be moreclearly and fully set forth in the following specification and claim.

loosening them. As a result the bolts often must In the drawings forminga part of our specifibe cut or drilled away, requiring considerablecation: valuable time and effort. With our apparatus Figure 1 is a sideelevational view of our screw most screws and bolts so anchored may beloosand bolt loosening device, a portion thereof being ened with asingle hammer 'blow, thus avoiding shown in section. the previousdifficulty. Figure 2 is a vertical section through the ap- A feature ofthe present invention lies in the paratus of Figure 1 on the line 2-2 ofFigure 1, provision of a screw and bolt loosening apparatus a differenthead being shown thereupon. including a handle portion and a cam portionFigure 3 is an elevation view of the cam portion connected thereto. Thehandle portion is conof our loosening device in one extreme position.nected to the cam portion in such a way that a Figure 4 is a viewsimilar to Figure 3 showing longitudinal blow on the handle portion willthe cam portion of the loosening device in its cause a twisting movementof the cam portion, other extreme position. thus transferring a sharpblow into a sudden The screw and bolt loosening device Aincludestwisting movement. This twisting movement is a handle I, a cam elementindicated in general usually sufiicient to loosen bolts or screws. bythe numeral H, and a head portion indicated A feature of the presentinvention lies in the in general by the numeral l2. The head I2 is factthat the cam portion of the apparatus is removable and replaceable witha head of a diflargely enclosed within the handle portion thereferentsize or shape. f. thus pr v n n inj ry o h h s f he The handle portionIll comprises an elongated p ra or during the operation of our to Th 39shank is preferably being knurled or otherwise Cam portion is Connectedto e a e po roughened on its exterior surface as indicated at by meansof a transverse bar which is secured in [4, h u er extremity of thehandle I3 is fixed relation to the handle. An inclined slot preferablyprovided with a portion l5 of reduced is provided through each side ofthe cam portion. diameter terminating in a tapered upper exp n l nitudinal movement of h handle tremity Hi. The upper extremity I6 isprovided tion relative to the cam portion, the cam will be with a flat rslightly rounded end surface I! forced in a rotative direction by thepin, thus which may b t k by a hammer or other per... c n he r q iredtwistin ction- The cam cussion instrument. The handle body In is proi pi d with n a so ke in he h le, an vided with a coaxial socket [9 whichextends a in x l a nt th reW th- Thus the force o considerable distanceinto the handle from the the W is C t ed c y p the AS lower end thereofon the end opposite the surface the cam is centered with the bolt orscrew loosen- H. The cam element ll fits snugly within the ing tool, theblow is transmitted centrally thereto, socket I 9 and is slidable androtatable therein. thus holding the tool in place during its rotative Anaperture 2|] is provided in the handle body movement. at the base of thesocket I9, and a second aper- A feature of the present invention lies inthe ture 2! is provided in the inner extremity of the provision of atorsion spring interposed between v cam element I I. Atorsion spring 22is positioned the handle and the cam portion. This torsion in the socketit] having one end 23 thereof anspring tends to hold the cam portion inprojected chored in the aperture 20 and the other end 24 position readyto be twisted by a relative longithereof anchored in the aperture 2!.The tortudinal movement between the handle portion sion spring tends tourge the cam element II in and the cam portion. one rotative positionfor a purpose which will be A further feature of the present inventionlies later described in detail. in providing a multi-sided axial lug onthe cam The cam element ll comprises an upper end portion of any tooldesigned to be accommodated 25, preferably formed in the shape of asleeve Figure 4 of the drawings.

3 having an axial recess 26 therein. This sleeve 25 is provided with apair of inclined slots 21 in the wall thereof. A pin 29 extends throughthe handle l near the lower extremity thereof and extends through theslots 21 in the sleeve 25. The slots 21 are so arranged as to guide thecam element l l in a rotary direction as the pin moves through thelength of the .slots 21. In other words, longitudinal movement of thecam element ll relative to the handle l0 will cause the cam element torotate throughout a predetermined angular distance. The torsion spring22 is so constructed and arranged as to urge the camelement outwardly ofthe handle 7 H]. In other words, the cam element 1 I normally projectsfrom the handle I0 in the manner illustrated in Figures 1, 2, and 3 ofthe drawings. However, if the cam element H is held from longitudinalmovement and the end 11 of the handle is struck with a hammer-or similarinstrument the cam element I will be rotated into'theqpositionillustrated'in At the completion of the blow the spring 22 will tendt'o'urge the-cam element ll into its original projected position asshown in Figures 1,2, an'd'3.

.The outer end of the cam element H is provided with a multi-sidedprojecting lug or shank which is engageable in a similarly shaped socket3| of the bolt or nut engaging device l2. As illustrated in Figure'l ofthe drawings this device 12 may be provided with an enlarged end 32having .a, multi-sided socket 33 therein for accommodating a nut or theheadof a bolt. Alternatively as illustrated in Figure 2"o"i the drawingsthe nut looseningdevice I I may be removed and the element 12substituted'therefor. The element [2 includes'a multi 'sided socket 34identical to the socket 3i and designed to receive the shank 30. Thedevice I2 also includes a shank 35 aligned with the socket 34and'bearing a wedge shaped end 36 in the nature of a screw driver. Theelement 12' may be used for loosening screws having slots therein byengaging the wedge shaped head 36 in the "slot of the screw driver andcausing rotation thereof.

The operation of our'tool i believed obvious from the foregoingdescription. The'shank-iiii is fitted with a suitable element 12 or ['2'to fit the nut, bolt head, or screw'slotof the-bolt or screw to beloosened. The tool is then applied to the element to be loosenedbyeither engaging the bolt head or nut in thesocket 33 or by engagingthe wedge end 36 of the element 12' in the screw slot. The handle II] isthen firmly held with one hand while the end ll of 'thehandle is strucka sharp blow with a hammer or similar tool. The force of the blow tendsto move the handle l0 toward the bolt or screw to :be loosened. As thecam element H is held from longitudinal movement, relative movement ofthe handle 10 will cause the head l2 or l2 to be rotated. Sufficientleverage is obtained in this way to loosen most nuts or bolts which havebeen rusted or otherwise become adhered in place.

It will be noted that the slots 21 are enclosed within the socket I9andthat all of the exposed portions of the handle andscam element aresubstantially cylindrical. Thus the sudden rotative .foroe will have notendency to catch the gloves or fingers of the operator to cause injurythereto. The slots 2! are arranged at a substantial angle to a planeperpendicular to the axis of the tool so that aconsiderable rotativeforce is exerted upon the tool head.

In accordance with the patent statutes, we have described the principlesof construction and operation of our screw and bolt loosening device,and while we have ende vored to set forth thebest'embodiment thereof, wedesire to'have it understood that-"obviouschangesmaybe made within thescope of the'following claim without departing from the'spirit'ofourinvention.

We claim:

An axial impact type rotary tool for loosening a threaded member-andincluding a handle elementfa socket in one end thereof, a, cam elementslidably and rotatably supported in said socket, 'a pin extendingthrough said handle element transversely of said'socket and normally=fixed relative theretoysaid cam element having cam slot meanstherein'throughwhich the pin-extends, said cam slot'means acting torotate'the cam element uponaxial movement'thereof relative to saidhandle element.

PAUL H. CARLSON. EDWIN N."CARLSON.

WARREN E. CARLSON.

REFERENCES CITED ".The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,384,417 .Weichhart July 12,1921 1,731,979 Krummel Oct. 15, 1929 1,742,040 Lynch Dec. '31, 19291,743,505 Turgeon Jan. 14, 1930 1,772,723 Klein Aug. 12, 1930 2,078,631Gagne Apr. 27, 1937 FOREIGN PATENTS Number Country Date 803,270 FranceJune 29, 1936 343,400 Italy Sept. 28, 1936 531,797 Great Britain Jan.10,1941

